Fast inverse kinematics and kinetics solver for human-like figures

Applying complex motions to humanoids involves to deal with different kinematic, kinetic and dynamic constraints. Although dynamics is more accurate to simulate humanoids, inverse kinematics is an alternative to rapidly calculate plausible movements required for motion planning. Humanoids motion planning that deals with numerous degrees of freedom requires numerous calls to inverse kinematics solvers that make computation time increase significantly. We propose a new approach that is able to solve complex character positioning while dealing with the center of mass position with very few computation time. An iterative hierarchical process is proposed: analytical solutions are proposed for groups of body segments while a higher solver is applied to drive the whole body and is repeated until stability is reached. With such a system, we are able to animate from 22 to 177 characters at 30 Hz on a classical P4 computer